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    <meta charset="UTF-8">
    <title>Document</title>
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    <h1>JS 函数</h1>
    <hr>

    <script>
        function demo() {
            console.log('demo....');
            return '12345';
        }

        var a = demo();  // 函数调用
        var b = demo;    // 函数的引用

        console.log(a);
        console.log(b);
        console.log(b());

    </script>
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